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Discussion Starter #1
Hi Fellas, I'm looking for thoughts on the ring gaps of a recent combo of mine. I tore the engine down this past spring and found the rings gaps set to 0.045" +/- on the Top ring. The bore size is 4.350". This was supposed to be set up for a 500 shot, but I'm concerned the gaps were set too wide?

Any input would be greatly appreciated

FWIW, when i did a leakdown, all cylinders were 30%.

Thanks
 

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WOW that's crazy big!!
 

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I agree that is a lot of ring gap, but I have never saw a problem from it. I have ran a .040 ring gap on a 4.060 bore just to see for myself what it would do and no issues. Sprayed a lot of nitrous on it and always did a leak down and it was sealed up good, no blow by, nothing. it's much better to have a lil too much gap then not enough. when it's too tight you can pull the pin out of the bottom of the piston when the ends but and the piston stops in the cyl and the crank keep turning!! lol
 

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you had more issues than ring gap if you had 30% leakage. i have had much less leakage than that and had a broke top ring on a cylinder.
 

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Discussion Starter #6
Thanks for your replies. Yes, there was many things wrong with the motor. I'm also not 100% confident the o-rings and head gaskets were sealing properly. The valves appeared to be sealing good on the seats, but maybe not? IDK...:(
 

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Hi Fellas, I'm looking for thoughts on the ring gaps of a recent combo of mine. I tore the engine down this past spring and found the rings gaps set to 0.045" +/- on the Top ring. The bore size is 4.350". This was supposed to be set up for a 500 shot, but I'm concerned the gaps were set too wide?

Any input would be greatly appreciated

FWIW, when i did a leakdown, all cylinders were 30%.

Thanks

Just curious as to how many passes or run time were on the engine ?? I have seen the ring gaps open over time and wear and surprise a few as well.. Thanks, SJ
 

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The second ring needs the larger gap so pressure cannot build up between the rings and unseat the top ring. The pressure must escape the second ring so the combustion pressure can keep the top ring sealed against the land below it.
 

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different ring makers say diff things. I think there is more ways than one to get the job done with good results, just from what I have delt with I have never saw too much ring gap hurt anything. IMOP the cylinder being round and straight with a nice finish is much more important. get the perfict ring gap in a cylinder that is shaped like an egg or an ice cream cone and you will have problems. Thats just my feeling from what I have had my hands on myself. People get caught up in ring gap because it is easy to measure and can over look the cylinder itself or how well the ring fits in the piston.
 

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one thing to keep in mind, if the shop wonders about your tuneing ability they may add a lil gap to the rings to cover their buts a lil. I have done this when I know the customer is gonna slap on a plate put the big pills in and not run the best fuel and half ass check the timing. I do all I can to help the engine live but in the end it is the customer who has to see that its tuned properly. Be nice to hear the engine shops side of the story and their take on things.
 

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Discussion Starter #17 (Edited)
one thing to keep in mind, if the shop wonders about your tuneing ability they may add a lil gap to the rings to cover their buts a lil. I have done this when I know the customer is gonna slap on a plate put the big pills in and not run the best fuel and half ass check the timing. I do all I can to help the engine live but in the end it is the customer who has to see that its tuned properly. Be nice to hear the engine shops side of the story and their take on things.

I can understand that. It appears as though the gaps were set too large, but that it wasn't really a big deal.

As far as the engine shop/builder, I never questioned him regarding the ring gaps. I had so many other things I was trying to resolve with him, I never got that far.

Thank you
 
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